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diff --git a/docs/busybox.net/programming.html b/docs/busybox.net/programming.html deleted file mode 100644 index b73e6ef..0000000 --- a/docs/busybox.net/programming.html +++ /dev/null @@ -1,584 +0,0 @@ -<!--#include file="header.html" --> - -<h2>Rob's notes on programming busybox.</h2> - -<ul> - <li><a href="#goals">What are the goals of busybox?</a></li> - <li><a href="#design">What is the design of busybox?</a></li> - <li><a href="#source">How is the source code organized?</a></li> - <ul> - <li><a href="#source_applets">The applet directories.</a></li> - <li><a href="#source_libbb">The busybox shared library (libbb)</a></li> - </ul> - <li><a href="#adding">Adding an applet to busybox</a></li> - <li><a href="#standards">What standards does busybox adhere to?</a></li> - <li><a href="#portability">Portability.</a></li> - <li><a href="#tips">Tips and tricks.</a></li> - <ul> - <li><a href="#tips_encrypted_passwords">Encrypted Passwords</a></li> - <li><a href="#tips_vfork">Fork and vfork</a></li> - <li><a href="#tips_short_read">Short reads and writes</a></li> - <li><a href="#tips_memory">Memory used by relocatable code, PIC, and static linking.</a></li> - <li><a href="#tips_kernel_headers">Including Linux kernel headers.</a></li> - </ul> - <li><a href="#who">Who are the BusyBox developers?</a></li> -</ul> - -<h2><b><a name="goals">What are the goals of busybox?</a></b></h2> - -<p>Busybox aims to be the smallest and simplest correct implementation of the -standard Linux command line tools. First and foremost, this means the -smallest executable size we can manage. We also want to have the simplest -and cleanest implementation we can manage, be <a href="#standards">standards -compliant</a>, minimize run-time memory usage (heap and stack), run fast, and -take over the world.</p> - -<h2><b><a name="design">What is the design of busybox?</a></b></h2> - -<p>Busybox is like a swiss army knife: one thing with many functions. -The busybox executable can act like many different programs depending on -the name used to invoke it. Normal practice is to create a bunch of symlinks -pointing to the busybox binary, each of which triggers a different busybox -function. (See <a href="FAQ.html#getting_started">getting started</a> in the -FAQ for more information on usage, and <a href="BusyBox.html">the -busybox documentation</a> for a list of symlink names and what they do.) - -<p>The "one binary to rule them all" approach is primarily for size reasons: a -single multi-purpose executable is smaller then many small files could be. -This way busybox only has one set of ELF headers, it can easily share code -between different apps even when statically linked, it has better packing -efficiency by avoding gaps between files or compression dictionary resets, -and so on.</p> - -<p>Work is underway on new options such as "make standalone" to build separate -binaries for each applet, and a "libbb.so" to make the busybox common code -available as a shared library. Neither is ready yet at the time of this -writing.</p> - -<a name="source"></a> - -<h2><a name="source_applets"><b>The applet directories</b></a></h2> - -<p>The directory "applets" contains the busybox startup code (applets.c and -busybox.c), and several subdirectories containing the code for the individual -applets.</p> - -<p>Busybox execution starts with the main() function in applets/busybox.c, -which sets the global variable bb_applet_name to argv[0] and calls -run_applet_by_name() in applets/applets.c. That uses the applets[] array -(defined in include/busybox.h and filled out in include/applets.h) to -transfer control to the appropriate APPLET_main() function (such as -cat_main() or sed_main()). The individual applet takes it from there.</p> - -<p>This is why calling busybox under a different name triggers different -functionality: main() looks up argv[0] in applets[] to get a function pointer -to APPLET_main().</p> - -<p>Busybox applets may also be invoked through the multiplexor applet -"busybox" (see busybox_main() in applets/busybox.c), and through the -standalone shell (grep for STANDALONE_SHELL in applets/shell/*.c). -See <a href="FAQ.html#getting_started">getting started</a> in the -FAQ for more information on these alternate usage mechanisms, which are -just different ways to reach the relevant APPLET_main() function.</p> - -<p>The applet subdirectories (archival, console-tools, coreutils, -debianutils, e2fsprogs, editors, findutils, init, loginutils, miscutils, -modutils, networking, procps, shell, sysklogd, and util-linux) correspond -to the configuration sub-menus in menuconfig. Each subdirectory contains the -code to implement the applets in that sub-menu, as well as a Config.in -file defining that configuration sub-menu (with dependencies and help text -for each applet), and the makefile segment (Makefile.in) for that -subdirectory.</p> - -<p>The run-time --help is stored in usage_messages[], which is initialized at -the start of applets/applets.c and gets its help text from usage.h. During the -build this help text is also used to generate the BusyBox documentation (in -html, txt, and man page formats) in the docs directory. See -<a href="#adding">adding an applet to busybox</a> for more -information.</p> - -<h2><a name="source_libbb"><b>libbb</b></a></h2> - -<p>Most non-setup code shared between busybox applets lives in the libbb -directory. It's a mess that evolved over the years without much auditing -or cleanup. For anybody looking for a great project to break into busybox -development with, documenting libbb would be both incredibly useful and good -experience.</p> - -<p>Common themes in libbb include allocation functions that test -for failure and abort the program with an error message so the caller doesn't -have to test the return value (xmalloc(), xstrdup(), etc), wrapped versions -of open(), close(), read(), and write() that test for their own failures -and/or retry automatically, linked list management functions (llist.c), -command line argument parsing (getopt_ulflags.c), and a whole lot more.</p> - -<h2><a name="adding"><b>Adding an applet to busybox</b></a></h2> - -<p>To add a new applet to busybox, first pick a name for the applet and -a corresponding CONFIG_NAME. Then do this:</p> - -<ul> -<li>Figure out where in the busybox source tree your applet best fits, -and put your source code there. Be sure to use APPLET_main() instead -of main(), where APPLET is the name of your applet.</li> - -<li>Add your applet to the relevant Config.in file (which file you add -it to determines where it shows up in "make menuconfig"). This uses -the same general format as the linux kernel's configuration system.</li> - -<li>Add your applet to the relevant Makefile.in file (in the same -directory as the Config.in you chose), using the existing entries as a -template and the same CONFIG symbol as you used for Config.in. (Don't -forget "needlibm" or "needcrypt" if your applet needs libm or -libcrypt.)</li> - -<li>Add your applet to "include/applets.h", using one of the existing -entries as a template. (Note: this is in alphabetical order. Applets -are found via binary search, and if you add an applet out of order it -won't work.)</li> - -<li>Add your applet's runtime help text to "include/usage.h". You need -at least appname_trivial_usage (the minimal help text, always included -in the busybox binary when this applet is enabled) and appname_full_usage -(extra help text included in the busybox binary with -CONFIG_FEATURE_VERBOSE_USAGE is enabled), or it won't compile. -The other two help entry types (appname_example_usage and -appname_notes_usage) are optional. They don't take up space in the binary, -but instead show up in the generated documentation (BusyBox.html, -BusyBox.txt, and the man page BusyBox.1).</li> - -<li>Run menuconfig, switch your applet on, compile, test, and fix the -bugs. Be sure to try both "allyesconfig" and "allnoconfig" (and -"allbareconfig" if relevant).</li> - -</ul> - -<h2><a name="standards">What standards does busybox adhere to?</a></h2> - -<p>The standard we're paying attention to is the "Shell and Utilities" -portion of the <a href="http://www.opengroup.org/onlinepubs/009695399/">Open -Group Base Standards</a> (also known as the Single Unix Specification version -3 or SUSv3). Note that paying attention isn't necessarily the same thing as -following it.</p> - -<p>SUSv3 doesn't even mention things like init, mount, tar, or losetup, nor -commonly used options like echo's '-e' and '-n', or sed's '-i'. Busybox is -driven by what real users actually need, not the fact the standard believes -we should implement ed or sccs. For size reasons, we're unlikely to include -much internationalization support beyond UTF-8, and on top of all that, our -configuration menu lets developers chop out features to produce smaller but -very non-standard utilities.</p> - -<p>Also, Busybox is aimed primarily at Linux. Unix standards are interesting -because Linux tries to adhere to them, but portability to dozens of platforms -is only interesting in terms of offering a restricted feature set that works -everywhere, not growing dozens of platform-specific extensions. Busybox -should be portable to all hardware platforms Linux supports, and any other -similar operating systems that are easy to do and won't require much -maintenance.</p> - -<p>In practice, standards compliance tends to be a clean-up step once an -applet is otherwise finished. When polishing and testing a busybox applet, -we ensure we have at least the option of full standards compliance, or else -document where we (intentionally) fall short.</p> - -<h2><a name="portability">Portability.</a></h2> - -<p>Busybox is a Linux project, but that doesn't mean we don't have to worry -about portability. First of all, there are different hardware platforms, -different C library implementations, different versions of the kernel and -build toolchain... The file "include/platform.h" exists to centralize and -encapsulate various platform-specific things in one place, so most busybox -code doesn't have to care where it's running.</p> - -<p>To start with, Linux runs on dozens of hardware platforms. We try to test -each release on x86, x86-64, arm, power pc, and mips. (Since qemu can handle -all of these, this isn't that hard.) This means we have to care about a number -of portability issues like endianness, word size, and alignment, all of which -belong in platform.h. That header handles conditional #includes and gives -us macros we can use in the rest of our code. At some point in the future -we might grow a platform.c, possibly even a platform subdirectory. As long -as the applets themselves don't have to care.</p> - -<p>On a related note, we made the "default signedness of char varies" problem -go away by feeding the compiler -funsigned-char. This gives us consistent -behavior on all platforms, and defaults to 8-bit clean text processing (which -gets us halfway to UTF-8 support). NOMMU support is less easily separated -(see the tips section later in this document), but we're working on it.</p> - -<p>Another type of portability is build environments: we unapologetically use -a number of gcc and glibc extensions (as does the Linux kernel), but these have -been picked up by packages like uClibc, TCC, and Intel's C Compiler. As for -gcc, we take advantage of newer compiler optimizations to get the smallest -possible size, but we also regression test against an older build environment -using the Red Hat 9 image at "http://busybox.net/downloads/qemu". This has a -2.4 kernel, gcc 3.2, make 3.79.1, and glibc 2.3, and is the oldest -build/deployment environment we still put any effort into maintaining. (If -anyone takes an interest in older kernels you're welcome to submit patches, -but the effort would probably be better spent -<a href="http://www.selenic.com/linux-tiny/">trimming -down the 2.6 kernel</a>.) Older gcc versions than that are uninteresting since -we now use c99 features, although -<a href="http://fabrice.bellard.free.fr/tcc/">tcc</a> might be worth a -look.</p> - -<p>We also test busybox against the current release of uClibc. Older versions -of uClibc aren't very interesting (they were buggy, and uClibc wasn't really -usable as a general-purpose C library before version 0.9.26 anyway).</p> - -<p>Other unix implementations are mostly uninteresting, since Linux binaries -have become the new standard for portable Unix programs. Specifically, -the ubiquity of Linux was cited as the main reason the Intel Binary -Compatability Standard 2 died, by the standards group organized to name a -successor to ibcs2: <a href="http://www.telly.org/86open/">the 86open -project</a>. That project disbanded in 1999 with the endorsement of an -existing standard: Linux ELF binaries. Since then, the major players at the -time (such as <a -href=http://www-03.ibm.com/servers/aix/products/aixos/linux/index.html>AIX</a>, <a -href=http://www.sun.com/software/solaris/ds/linux_interop.jsp#3>Solaris</a>, and -<a href=http://www.onlamp.com/pub/a/bsd/2000/03/17/linuxapps.html>FreeBSD</a>) -have all either grown Linux support or folded.</p> - -<p>The major exceptions are newcomer MacOS X, some embedded environments -(such as newlib+libgloss) which provide a posix environment but not a full -Linux environment, and environments like Cygwin that provide only partial Linux -emulation. Also, some embedded Linux systems run a Linux kernel but amputate -things like the /proc directory to save space.</p> - -<p>Supporting these systems is largely a question of providing a clean subset -of BusyBox's functionality -- whichever applets can easily be made to -work in that environment. Annotating the configuration system to -indicate which applets require which prerequisites (such as procfs) is -also welcome. Other efforts to support these systems (swapping #include -files to build in different environments, adding adapter code to platform.h, -adding more extensive special-case supporting infrastructure such as mount's -legacy mtab support) are handled on a case-by-case basis. Support that can be -cleanly hidden in platform.h is reasonably attractive, and failing that -support that can be cleanly separated into a separate conditionally compiled -file is at least worth a look. Special-case code in the body of an applet is -something we're trying to avoid.</p> - -<h2><a name="tips" />Programming tips and tricks.</a></h2> - -<p>Various things busybox uses that aren't particularly well documented -elsewhere.</p> - -<h2><a name="tips_encrypted_passwords">Encrypted Passwords</a></h2> - -<p>Password fields in /etc/passwd and /etc/shadow are in a special format. -If the first character isn't '$', then it's an old DES style password. If -the first character is '$' then the password is actually three fields -separated by '$' characters:</p> -<pre> - <b>$type$salt$encrypted_password</b> -</pre> - -<p>The "type" indicates which encryption algorithm to use: 1 for MD5 and 2 for SHA1.</p> - -<p>The "salt" is a bunch of ramdom characters (generally 8) the encryption -algorithm uses to perturb the password in a known and reproducible way (such -as by appending the random data to the unencrypted password, or combining -them with exclusive or). Salt is randomly generated when setting a password, -and then the same salt value is re-used when checking the password. (Salt is -thus stored unencrypted.)</p> - -<p>The advantage of using salt is that the same cleartext password encrypted -with a different salt value produces a different encrypted value. -If each encrypted password uses a different salt value, an attacker is forced -to do the cryptographic math all over again for each password they want to -check. Without salt, they could simply produce a big dictionary of commonly -used passwords ahead of time, and look up each password in a stolen password -file to see if it's a known value. (Even if there are billions of possible -passwords in the dictionary, checking each one is just a binary search against -a file only a few gigabytes long.) With salt they can't even tell if two -different users share the same password without guessing what that password -is and decrypting it. They also can't precompute the attack dictionary for -a specific password until they know what the salt value is.</p> - -<p>The third field is the encrypted password (plus the salt). For md5 this -is 22 bytes.</p> - -<p>The busybox function to handle all this is pw_encrypt(clear, salt) in -"libbb/pw_encrypt.c". The first argument is the clear text password to be -encrypted, and the second is a string in "$type$salt$password" format, from -which the "type" and "salt" fields will be extracted to produce an encrypted -value. (Only the first two fields are needed, the third $ is equivalent to -the end of the string.) The return value is an encrypted password in -/etc/passwd format, with all three $ separated fields. It's stored in -a static buffer, 128 bytes long.</p> - -<p>So when checking an existing password, if pw_encrypt(text, -old_encrypted_password) returns a string that compares identical to -old_encrypted_password, you've got the right password. When setting a new -password, generate a random 8 character salt string, put it in the right -format with sprintf(buffer, "$%c$%s", type, salt), and feed buffer as the -second argument to pw_encrypt(text,buffer).</p> - -<h2><a name="tips_vfork">Fork and vfork</a></h2> - -<p>On systems that haven't got a Memory Management Unit, fork() is unreasonably -expensive to implement (and sometimes even impossible), so a less capable -function called vfork() is used instead. (Using vfork() on a system with an -MMU is like pounding a nail with a wrench. Not the best tool for the job, but -it works.)</p> - -<p>Busybox hides the difference between fork() and vfork() in -libbb/bb_fork_exec.c. If you ever want to fork and exec, use bb_fork_exec() -(which returns a pid and takes the same arguments as execve(), although in -this case envp can be NULL) and don't worry about it. This description is -here in case you want to know why that does what it does.</p> - -<p>Implementing fork() depends on having a Memory Management Unit. With an -MMU then you can simply set up a second set of page tables and share the -physical memory via copy-on-write. So a fork() followed quickly by exec() -only copies a few pages of the parent's memory, just the ones it changes -before freeing them.</p> - -<p>With a very primitive MMU (using a base pointer plus length instead of page -tables, which can provide virtual addresses and protect processes from each -other, but no copy on write) you can still implement fork. But it's -unreasonably expensive, because you have to copy all the parent process' -memory into the new process (which could easily be several megabytes per fork). -And you have to do this even though that memory gets freed again as soon as the -exec happens. (This is not just slow and a waste of space but causes memory -usage spikes that can easily cause the system to run out of memory.)</p> - -<p>Without even a primitive MMU, you have no virtual addresses. Every process -can reach out and touch any other process' memory, because all pointers are to -physical addresses with no protection. Even if you copy a process' memory to -new physical addresses, all of its pointers point to the old objects in the -old process. (Searching through the new copy's memory for pointers and -redirect them to the new locations is not an easy problem.)</p> - -<p>So with a primitive or missing MMU, fork() is just not a good idea.</p> - -<p>In theory, vfork() is just a fork() that writeably shares the heap and stack -rather than copying it (so what one process writes the other one sees). In -practice, vfork() has to suspend the parent process until the child does exec, -at which point the parent wakes up and resumes by returning from the call to -vfork(). All modern kernel/libc combinations implement vfork() to put the -parent to sleep until the child does its exec. There's just no other way to -make it work: the parent has to know the child has done its exec() or exit() -before it's safe to return from the function it's in, so it has to block -until that happens. In fact without suspending the parent there's no way to -even store separate copies of the return value (the pid) from the vfork() call -itself: both assignments write into the same memory location.</p> - -<p>One way to understand (and in fact implement) vfork() is this: imagine -the parent does a setjmp and then continues on (pretending to be the child) -until the exec() comes around, then the _exec_ does the actual fork, and the -parent does a longjmp back to the original vfork call and continues on from -there. (It thus becomes obvious why the child can't return, or modify -local variables it doesn't want the parent to see changed when it resumes.) - -<p>Note a common mistake: the need for vfork doesn't mean you can't have two -processes running at the same time. It means you can't have two processes -sharing the same memory without stomping all over each other. As soon as -the child calls exec(), the parent resumes.</p> - -<p>If the child's attempt to call exec() fails, the child should call _exit() -rather than a normal exit(). This avoids any atexit() code that might confuse -the parent. (The parent should never call _exit(), only a vforked child that -failed to exec.)</p> - -<p>(Now in theory, a nommu system could just copy the _stack_ when it forks -(which presumably is much shorter than the heap), and leave the heap shared. -Even with no MMU at all -In practice, you've just wound up in a multi-threaded situation and you can't -do a malloc() or free() on your heap without freeing the other process' memory -(and if you don't have the proper locking for being threaded, corrupting the -heap if both of you try to do it at the same time and wind up stomping on -each other while traversing the free memory lists). The thing about vfork is -that it's a big red flag warning "there be dragons here" rather than -something subtle and thus even more dangerous.)</p> - -<h2><a name="tips_sort_read">Short reads and writes</a></h2> - -<p>Busybox has special functions, bb_full_read() and bb_full_write(), to -check that all the data we asked for got read or written. Is this a real -world consideration? Try the following:</p> - -<pre>while true; do echo hello; sleep 1; done | tee out.txt</pre> - -<p>If tee is implemented with bb_full_read(), tee doesn't display output -in real time but blocks until its entire input buffer (generally a couple -kilobytes) is read, then displays it all at once. In that case, we _want_ -the short read, for user interface reasons. (Note that read() should never -return 0 unless it has hit the end of input, and an attempt to write 0 -bytes should be ignored by the OS.)</p> - -<p>As for short writes, play around with two processes piping data to each -other on the command line (cat bigfile | gzip > out.gz) and suspend and -resume a few times (ctrl-z to suspend, "fg" to resume). The writer can -experience short writes, which are especially dangerous because if you don't -notice them you'll discard data. They can also happen when a system is under -load and a fast process is piping to a slower one. (Such as an xterm waiting -on x11 when the scheduler decides X is being a CPU hog with all that -text console scrolling...)</p> - -<p>So will data always be read from the far end of a pipe at the -same chunk sizes it was written in? Nope. Don't rely on that. For one -counterexample, see <a href="http://www.faqs.org/rfcs/rfc896.html">rfc 896 -for Nagle's algorithm</a>, which waits a fraction of a second or so before -sending out small amounts of data through a TCP/IP connection in case more -data comes in that can be merged into the same packet. (In case you were -wondering why action games that use TCP/IP set TCP_NODELAY to lower the latency -on their their sockets, now you know.)</p> - -<h2><a name="tips_memory">Memory used by relocatable code, PIC, and static linking.</a></h2> - -<p>The downside of standard dynamic linking is that it results in self-modifying -code. Although each executable's pages are mmaped() into a process' address -space from the executable file and are thus naturally shared between processes -out of the page cache, the library loader (ld-linux.so.2 or ld-uClibc.so.0) -writes to these pages to supply addresses for relocatable symbols. This -dirties the pages, triggering copy-on-write allocation of new memory for each -processes' dirtied pages.</p> - -<p>One solution to this is Position Independent Code (PIC), a way of linking -a file so all the relocations are grouped together. This dirties fewer -pages (often just a single page) for each process' relocations. The down -side is this results in larger executables, which take up more space on disk -(and a correspondingly larger space in memory). But when many copies of the -same program are running, PIC dynamic linking trades a larger disk footprint -for a smaller memory footprint, by sharing more pages.</p> - -<p>A third solution is static linking. A statically linked program has no -relocations, and thus the entire executable is shared between all running -instances. This tends to have a significantly larger disk footprint, but -on a system with only one or two executables, shared libraries aren't much -of a win anyway.</p> - -<p>You can tell the glibc linker to display debugging information about its -relocations with the environment variable "LD_DEBUG". Try -"LD_DEBUG=help /bin/true" for a list of commands. Learning to interpret -"LD_DEBUG=statistics cat /proc/self/statm" could be interesting.</p> - -<p>For more on this topic, here's Rich Felker:</p> -<blockquote> -<p>Dynamic linking (without fixed load addresses) fundamentally requires -at least one dirty page per dso that uses symbols. Making calls (but -never taking the address explicitly) to functions within the same dso -does not require a dirty page by itself, but will with ELF unless you -use -Bsymbolic or hidden symbols when linking.</p> - -<p>ELF uses significant additional stack space for the kernel to pass all -the ELF data structures to the newly created process image. These are -located above the argument list and environment. This normally adds 1 -dirty page to the process size.</p> - -<p>The ELF dynamic linker has its own data segment, adding one or more -dirty pages. I believe it also performs relocations on itself.</p> - -<p>The ELF dynamic linker makes significant dynamic allocations to manage -the global symbol table and the loaded dso's. This data is never -freed. It will be needed again if libdl is used, so unconditionally -freeing it is not possible, but normal programs do not use libdl. Of -course with glibc all programs use libdl (due to nsswitch) so the -issue was never addressed.</p> - -<p>ELF also has the issue that segments are not page-aligned on disk. -This saves up to 4k on disk, but at the expense of using an additional -dirty page in most cases, due to a large portion of the first data -page being filled with a duplicate copy of the last text page.</p> - -<p>The above is just a partial list of the tiny memory penalties of ELF -dynamic linking, which eventually add up to quite a bit. The smallest -I've been able to get a process down to is 8 dirty pages, and the -above factors seem to mostly account for it (but some were difficult -to measure).</p> -</blockquote> - -<h2><a name="tips_kernel_headers"></a>Including kernel headers</h2> - -<p>The "linux" or "asm" directories of /usr/include contain Linux kernel -headers, so that the C library can talk directly to the Linux kernel. In -a perfect world, applications shouldn't include these headers directly, but -we don't live in a perfect world.</p> - -<p>For example, Busybox's losetup code wants linux/loop.c because nothing else -#defines the structures to call the kernel's loopback device setup ioctls. -Attempts to cut and paste the information into a local busybox header file -proved incredibly painful, because portions of the loop_info structure vary by -architecture, namely the type __kernel_dev_t has different sizes on alpha, -arm, x86, and so on. Meaning we either #include <linux/posix_types.h> or -we hardwire #ifdefs to check what platform we're building on and define this -type appropriately for every single hardware architecture supported by -Linux, which is simply unworkable.</p> - -<p>This is aside from the fact that the relevant type defined in -posix_types.h was renamed to __kernel_old_dev_t during the 2.5 series, so -to cut and paste the structure into our header we have to #include -<linux/version.h> to figure out which name to use. (What we actually do is -check if we're building on 2.6, and if so just use the new 64 bit structure -instead to avoid the rename entirely.) But we still need the version -check, since 2.4 didn't have the 64 bit structure.</p> - -<p>The BusyBox developers spent <u>two years</u> _two years_ trying to figure -out a clean way to do all this. There isn't one. The losetup in the -util-linux package from kernel.org isn't doing it cleanly either, they just -hide the ugliness by nesting #include files. Their mount/loop.h -#includes "my_dev_t.h", which #includes <linux/posix_types.h> and -<linux/version.h> just like we do. There simply is no alternative.</p> - -<p>We should never directly include kernel headers when there's a better -way to do it, but block copying information out of the kernel headers is not -a better way.</p> - -<h2><a name="who">Who are the BusyBox developers?</a></h2> - -<p>The following login accounts currently exist on busybox.net. (I.E. these -people can commit <a href="http://busybox.net/downloads/patches">patches</a> -into subversion for the BusyBox, uClibc, and buildroot projects.)</p> - -<pre> -aldot :Bernhard Fischer -andersen :Erik Andersen <- uClibc and BuildRoot maintainer. -bug1 :Glenn McGrath -davidm :David McCullough -gkajmowi :Garrett Kajmowicz <- uClibc++ maintainer -jbglaw :Jan-Benedict Glaw -jocke :Joakim Tjernlund -landley :Rob Landley <- BusyBox maintainer -lethal :Paul Mundt -mjn3 :Manuel Novoa III -osuadmin :osuadmin -pgf :Paul Fox -pkj :Peter Kjellerstedt -prpplague :David Anders -psm :Peter S. Mazinger -russ :Russ Dill -sandman :Robert Griebl -sjhill :Steven J. Hill -solar :Ned Ludd -timr :Tim Riker -tobiasa :Tobias Anderberg -vapier :Mike Frysinger -</pre> - -<p>The following accounts used to exist on busybox.net, but don't anymore so -I can't ask /etc/passwd for their names. (If anybody would like to make -a stab at it...)</p> - -<pre> -aaronl -beppu -dwhedon -erik : Also Erik Andersen? -gfeldman -jimg -kraai -markw -miles -proski -rjune -tausq -vodz :Vladimir N. Oleynik -</pre> - - -<br> -<br> -<br> - -<!--#include file="footer.html" --> |